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81.
An interspecific artificial hybrid was produced between two economically important aquaculture flatfish: olive flounder (Paralichthys olivaceus) and starry flounder (P. stellatus). This hybrid displays the rapid growth characteristic of the former and tolerance to low temperatures and low salinity of the latter, but the genetics of inheritance in this hybrid have not been elucidated. Polymorphic microsatellite markers developed for P. olivaceus and P. stellatus were tested to determine if these markers can be used for analysis of parentage and genetic inheritance. Multiplex PCR using two primer sets that were specific to each species produced PCR products of different sizes; these could be used for the identification of interspecific hybrids. Among the 192 primers derived from olive flounder, 25.5% of the primer sets successfully amplified genomic DNA from starry flounder, and 23% of the 56 primer sets originating from starry flounder amplified DNA from olive flounder. Analysis of genetic inheritance in the hybrid using seven of the 62 microsatellite markers common to both species demonstrated classic Mendelian inheritance of these markers in the hybrid progeny, with the exception of one locus identified as a null allele in the hybrid. These results demonstrate that cross-specific microsatellite markers can be used tools for parentage analysis of hybrid flatfish, for mapping quantitative trait loci, for marker-assisted selective breeding, and for studies of the evolution of fish.  相似文献   
82.
Mental retardation is the most common and debilitating condition for individuals with Down syndrome (DS). The hyper-activation of DYRK1A by overexpression causes significant learning and memory deficits in DS-model mice. Thus far, no mechanism-based drug has been developed to address this. After a combination of in silico and in vitro screenings, two DYRK1A inhibitors were isolated that are active in a cell-based assay. Further optimization could lead to a novel drug discovery that could address DS learning and memory deficits.  相似文献   
83.
Total 2,829 persons consisted of 1,019 general patients and 1,030 asthma-suspected patients who visited Kangnam St. Mary's Hospital and 780 general patients who visited Cheju Medical Center were examined for the antibody titers of Toxoplasma by indirect latex agglutination (ILA) test. Nineteen out of 1,019(1.86%) cases in general patients group, 11 out of 1,030(1.07%) cases in asthma patients group, and 45 out of 780(5.77%) cases in Cheju patients group showed positive ILA titers. Concerned with the age and ILA positive cases, general and asthma patients expressed more cases at thirties to sixties while Cheju patients showed high incidence at children and adolescents in addition to the above mentioned ages. Frequencies of ILA positive titers were highest in 1:32 and 1:64, and some cases showed 1:2,048 or higher titers.  相似文献   
84.
Follicles are important in oocyte maturation. Successful estrous cycle requires remodeling of follicular cells, and proper execution of programmed cell death is crucial for normal follicular development. The objectives of the present study were to understand programmed cell death during follicle development, to analyze the differential follicle development patterns, and to assess the patterns of apoptosis and autophagy expression during follicle development in normal and miniature pigs. Through the analysis of differential patterns of programmed cell death during follicular development in porcine, MAP1LC3A, B and other autophagy-associated genes (ATG5, mTOR, Beclin-1) were found to increase in normal pigs, while it decreased in miniature pigs. However, for the apoptosis-associated genes, progression of genes during follicular development increased in miniature pigs, while it decreased in normal pigs. Thus, results show that normal and miniature pigs showed distinct patterns of follicular remodeling manifesting that programmed cell death largely depends on the types of pathway during follicular development (Type II or autophagy for normal pigs and Type I or apoptosis for miniature pigs).  相似文献   
85.
Anaerobic bio-hydrogen production from ethanol fermentation: the role of pH   总被引:16,自引:0,他引:16  
Hydrogen was produced by an ethanol-acetate fermentation at pH of 5.0 +/- 0.2 and HRT of 3 days. The yield of hydrogen was 100-200 ml g Glu(-1) with a hydrogen content of 25-40%. This fluctuation in the hydrogen yield was attributed to the formation of propionate and the activity of hydrogen utilizing methanogens. The change in the operational pH for the inhibition of this methanogenic activity induced a change in the main fermentation pathway. In this study, the main products were butyrate, ethanol and propionate, in the pH ranges 4.0-4.5, 4.5-5.0 and 5.0-6.0, respectively. However, the activity of all the microorganisms was inhibited below pH 4.0. Therefore, pH 4.0 was regarded as the operational limit for the anaerobic bio-hydrogen production process. These results indicate that the pH plays an important role in determining the type of anaerobic fermentation pathway in anaerobic bio-hydrogen processes.  相似文献   
86.
87.
The domestic chicken (Gallus gallus) is an important model for research in developmental biology because its embryonic development occurs in ovo. To examine the mechanism of embryonic germ cell development, we constructed proteome map of gonadal primordial germ cells (gPGCs) from chicken embryonic gonads. Embryonic gonads were collected from 500 embryos at 6 days of incubation, and the gPGCs were cultured in vitro until colony formed. After 7-10 days in culture, gPGC colonies were separated from gonadal stroma cells (GSCs). Soluble extracts of cultured gPGCs were then fractionated by two-dimensional gel electrophoresis (pH 4-7). A number of protein spots, including those that displayed significant expression levels, were then identified by use of matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry and LC-MS/MS. Of the 89 gPGC spots examined, 50 yielded mass spectra that matched avian proteins found in on-line databases. Proteome map of this type will serve as an important reference for germ cell biology and transgenic research.  相似文献   
88.
The title compound, methyl 2-methoxy-7-(4-methylbenzoyl)-4-oxo-6-p-tolyl-4H-furo[3,2-c]pyran-3-carboxylate (C25H20O7), was prepared and characterized by IR and single-crystal X-ray diffraction (XRD). The compound crystallizes in the triclinic space group P ?1 with a?=?8.9554(9) Å, b?=?10.0018(10) Å, c?=?12.7454(13) Å, α?=?67.678(7)°, β?=?89.359(8)° and γ?=?88.961(8)°. In addition to the molecular geometry from X-ray experiment, the molecular geometry and vibrational frequencies of the title compound in the ground state have been calculated using semiempirical AM1 and PM3 methods, as well as Hartree-Fock (HF) and density functional (B3LYP) levels of theory with 6–31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 10°. Besides, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were performed by the B3LYP/6–31G(d) method.  相似文献   
89.
Kim JW  Nam SH  Jang KT  Lee SH  Kim CC  Hahn SH  Hu JC  Simmer JP 《Human genetics》2004,115(3):248-254
The dentin sialophosphoprotein (DSPP) gene (4q21.3) encodes two major noncollagenous dentin matrix proteins: dentin sialoprotein (DSP) and dentin phosphoprotein (DPP). Defects in the human gene encoding DSPP cause inherited dentin defects, and these defects can be associated with bilateral progressive high-frequency sensorineural hearing loss. Clinically, five different patterns of inherited dentin defects are distinguished and are classified as dentinogenesis imperfecta (DGI) types I, II, and III, and dentin dysplasia types I and II. The genetic basis for this clinical heterogeneity is unknown. Among the 11 members recruited from the studied kindred, five were affected with autosomal dominant DGI type II. The mutation (g.1188CG, IVS2-3CG) lay in the third from the last nucleotide of intron 2 and changed its sequence from CAG to GAG. The mutation was correlated with the affection status and was absent in 104 unaffected individuals (208 alleles) with the same ethnic and geological background. The proband was in the primary dentition stage and presented with multiple pulp exposures. The occlusal surface of his dental enamel was generally abraded, and the dentin was heavily worn and uniformly shaded brown. The dental pulp chambers appeared originally to be within normal limits without any sign of obliteration, but over time (by age 4), the pulp chambers became partially or completely obliterated. The oldest affected member (age 59) showed mild hearing loss at high-frequency (8 kHz). Permanent dentition was severely affected in the adults, who had advanced dental attrition, premature loss of teeth, and extensive dental reconstruction.  相似文献   
90.
The full three-dimensional structure of the catalytic domain of human collagenase-3 (MMP-13) complexed to a potent, sulfonamide hydroxamic acid inhibitor (CGS 27023) has been determined by NMR spectroscopy. The results reveal a core domain for the protein consisting of three alpha-helices and five beta-sheet strands with an overall tertiary fold similar to the catalytic domains of other matrix metalloproteinase family members. The S1' pocket, which is the major site of hydrophobic binding interaction, was found to be a wide cleft spanning the length of the protein and presenting facile opportunity for inhibitor extension deep into the pocket. Comparison with the reported X-ray structure of collagenase-3 showed evidence of flexibility for the loop region flanking the S1' pocket in both NMR and X-ray data. This flexibility was corroborated by NMR dynamics studies. Inhibitor binding placed the methoxy phenyl ring in the S1' pocket with the remainder of the molecule primarily solvent-exposed. The binding mode for this inhibitor was found to be similar with respect to stromelysin-1 and collagenase-1; however, subtle comparative differences in the interactions between inhibitor and enzyme were observed for the three MMPs that were consistent with their respective binding potencies.  相似文献   
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